There has been a prior technology known to public for a sun roof device of a vehicle equipped with a device, which stops the roof panel that is closing or moves it in the reverse direction to open on detecting a load applied to the roof when an obstacle like a hand hits the roof panel. However this device can not prevent the obstacle from coming in contact with the roof panel because the device works only when a load larger than predetermined is applied to the roof panel.
Alternatively, Japanese Laid-Open Patent Application No. 2003-278443 discloses a technology in which is provided a distance detecting device for detecting a distance between an opening-closing unit of a vehicle and the obstacle, and this device stops the opening-closing unit or reverses the direction in which the opening-closing unit moves, based on the distance detected thereof. Therefore, it is possible to prevent the obstacle from coming in contact with the sun roof panel by utilizing this technology and the safety for the roof panel is expected to improve because an accident like a hand getting caught in the roof panel device can be prevented.
Explaining an embodiment in Japanese Laid-Open Patent Application No. 2003-278443 by using codes in the document, as explained in the paragraph 0033, a closure distance, Ls, from a closing edge 5 of a slide door 3 to an opening side 6 which is detected by ultrasonic sensors 21, 22 and 23, is compared with a distance from a closing edge 5 to an opening side 6 which is measured by a pulse signal outputted from a hole IC 14. If both distances are equal, it is determined that there is no obstacle 24. If the distance of Ls is shorter than that of the latter distance, it is determined that there is an obstacle 24.